Multi-piece epitaxial furnace chamber structure

Abstract

The invention relates to the technical field of epitaxial wafer growth, and particularly discloses a multi-wafer epitaxial furnace chamber structure, which is characterized in that a plurality of small bases which are in running fit with a large base are arranged on the large base, and a tray which can be used for placing a substrate raw material growth epitaxial wafer is placed on each small base; a plurality of small bases are arranged in the large base, a plurality of air channel structures are further arranged in the large base, and each air channel structure correspondingly drives one small base to rotate, so that when epitaxial wafers are produced, due to the fact that each air channel structure can independently drive the corresponding small base to rotate, and when the substrates are placed on trays located above the small bases to grow the epitaxial wafers, the epitaxial wafers can be produced. Therefore, synchronous production of a plurality of epitaxial wafers can be realized at the same time, so that the production efficiency is improved; and each small base is driven to rotate by air supply of an independent air channel structure, so that the temperature and flow field distribution uniformity of the surface of each epitaxial wafer can be ensured, the growth uniformity of the epitaxial wafer is ensured, and the production quality is further improved.

Description

Technical Field

[0001] The invention relates to the technical field of epitaxial wafer growth, and in particular to a multi-wafer epitaxial furnace chamber structure. Background Art

[0002] With the development of the semiconductor industry, the demand for epitaxial wafers has greatly increased, and the quality requirements for epitaxial wafers have also gradually increased. Therefore, improving the growth efficiency and quality of epitaxial wafers is an important development trend. At present, epitaxial growth mostly adopts vapor phase epitaxy. When a single wafer is produced, a hot wall horizontal chamber is mostly used. The quality of epitaxial wafers produced by this production method is relatively stable; when multiple wafers are produced, a warm wall planetary chamber is mostly used. This method can grow multiple epitaxial wafers at the same time, but due to the complex production structure of this production method, it is difficult to control product consistency. Therefore, how to grow multiple epitaxial wafers using hot wall horizontal growth is an important direction for achieving the simultaneous growth of multiple high-quality epitaxial wafers.

[0003] The technical problem to be solved by the present application is: to design a multi-wafer epitaxial furnace chamber structure capable of growing multiple epitaxial wafers simultaneously. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, an object of the present invention is to provide a multi-wafer epitaxial furnace chamber structure capable of growing multiple epitaxial wafers simultaneously.

[0005] The technical solution adopted by the present invention is: a multi-wafer epitaxial furnace chamber structure, including an upper heating ring and a lower heating ring connected to the upper heating ring, the lower heating ring is provided with a large base for rotating with the upper heating ring, the large base is provided with a plurality of small bases for rotating with the upper heating ring, each small base is provided with a tray for placing raw material growth epitaxial wafers, the large base is provided with a plurality of airway structures, each airway structure corresponds to driving a small base to rotate.

[0006] In some embodiments, the airway structure includes a plurality of longitudinal airways located inside the large base and transverse airways connected to the longitudinal airways, the transverse airways are provided with a plurality of air outlet holes connected to the upper surface of the large base, the airway structure also includes a plurality of first annular airway channels provided at the bottom of the large base, and the longitudinal airways are connected to the first annular airway channels.

[0007] In some embodiments, a plurality of strip grooves are provided at the bottom of the small base, and the strip grooves are arranged in a polar array at the bottom of the small base.

[0008] In some embodiments, the lower heating ring is provided with a plurality of annular grooves, and the bottom of the large base is provided with a plurality of convex rings corresponding to the annular grooves, the convex rings and the annular grooves are limitedly rotated together, and the first annular airflow channel is provided between adjacent convex rings.

[0009] In some embodiments, the lower heating ring is provided with a plurality of second annular airflow channels, and the second annular airflow channels are located between two adjacent annular grooves. Each second annular airflow channel is provided with an air inlet channel connected therewith, and the air inlet channel is connected to an external air source. After the convex ring and the annular groove are limitedly engaged, an annular airflow chamber is formed between the first annular airflow channel and the second annular airflow channel.

[0010] In some embodiments, a rotating shaft connected to the bottom of the large base is provided, and the rotating shaft passes through the lower heating ring and rotates with the lower heating ring.

[0011] In some embodiments, a plurality of limit grooves are provided on the surface of the large base, a latch is provided in the middle of each limit groove, the small base is located in the limit groove and is rotatably connected to the latch, and each air outlet end of the airway structure corresponds to a limit groove.

[0012] In some embodiments, the lower heating ring is also provided with an upstream protective plate, a downstream protective plate and a transition piece for the reaction gas to flow in, one end of the upstream protective plate is provided with a gas guide slope, the transition piece is provided with a gas passage cavity, and the gas guide slope is arranged corresponding to the gas passage cavity.

[0013] In some embodiments, the lower heating ring is further provided with a central protective plate at the end close to the downstream protective plate, the large base is located between the upstream protective plate, the downstream protective plate and the central protective plate, and side baffles are provided on both sides of the lower heating ring, and the upper ends of the side baffles are connected to the upper heating ring.

[0014] In some embodiments, a circumferential cover plate and a central cover plate are respectively provided on the upper surface of the large base, through holes are provided between the circumferential cover plate and the central cover plate corresponding to the limiting grooves, and an anti-slip ring is provided on the side of the small base, and the diameter of the anti-slip ring is larger than the diameter of the through hole.

[0015] The present invention has the following technical effects: a plurality of small bases are arranged on a large base to rotate with the large base, and a tray for placing substrate raw materials to grow epitaxial wafers is placed on each small base, and a plurality of airway structures are also arranged in the large base, and each airway structure drives a corresponding small base to rotate. In this way, when producing epitaxial wafers, since each airway structure can independently drive its corresponding small base to rotate, when the substrate is placed on the tray above the small base for epitaxial wafer growth, the synchronous production of multiple epitaxial wafers can be achieved at the same time, thereby improving production efficiency; and each small base is driven to rotate by air supply from a separate airway structure, so that the temperature and flow field on the surface of each epitaxial wafer can be guaranteed to be evenly distributed, thereby ensuring the growth uniformity of the epitaxial wafers and further improving production quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the chamber structure of a multi-wafer epitaxial furnace of the present invention;

[0017] Figure 2 It is a schematic diagram of the separation structure of the upper heating ring and the lower heating ring of the chamber structure of the multi-wafer epitaxial furnace of the present invention;

[0018] Figure 3 It is a schematic diagram of the explosion of the structure of the chamber structure of the multi-wafer epitaxial furnace of the present invention;

[0019] Figure 4 It is a schematic cross-sectional structure diagram of the chamber structure of a multi-wafer epitaxial furnace of the present invention;

[0020] Figure 5 It is a schematic diagram of the lower heating ring structure of the chamber structure of the multi-wafer epitaxial furnace of the present invention;

[0021] Figure 6 It is a schematic diagram of the bottom surface structure of the large base of the multi-wafer epitaxial furnace chamber structure of the present invention;

[0022] Figure 7 It is a schematic diagram of the bottom surface structure of the small base of the multi-wafer epitaxial furnace chamber structure of the present invention.

[0023] The numbers and names in the figure correspond to each other as follows: 1. upper heating ring; 2. lower heating ring; 3. large base; 4. small base; 5. tray; 30. longitudinal air duct; 31. transverse air duct; 32. air outlet; 33. first annular air duct; 40. strip groove; 20. annular groove; 34. convex ring; 21. second annular air duct; 22. air inlet; 23. annular air flow chamber; 35. rotating shaft; 36. limiting groove; 37. latch; 24. upstream protective plate; 25. downstream protective plate; 26. transition piece; 27. air guide slope; 28. air passage chamber; 29. ​​central protective plate; 6. side baffle; 7. circumferential cover plate; 8. central cover plate; 9. through hole; 41. anti-slip ring; 10. reaction chamber. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See also Figure 1-7The present invention provides a technical solution: a multi-wafer epitaxial furnace chamber structure, comprising an upper heating ring 1 and a lower heating ring 2 connected to the upper heating ring 1, a reaction chamber 10 for growing epitaxial wafers on the substrate surface is formed between the upper heating ring 1 and the lower heating ring 2, a large base 3 rotatably matched with the lower heating ring 2 is provided on the lower heating ring 2, and a plurality of small bases 4 rotatably matched with the large base 3 are provided on the large base 3, wherein each small base 4 is provided with a tray 5, and the surface of the tray 5 is mainly used for placing substrate raw materials for growing epitaxial wafers, so that by providing a plurality of separate small bases 4 on the large base 3, and placing a tray 5 for placing substrate raw materials on the surface of the small base 4, it is possible to realize the simultaneous production of multiple epitaxial wafers, greatly improving the production efficiency, and a plurality of airway structures are also provided in the large base 3, wherein each airway structure corresponds to the air supply to drive a small base 4 to rotate, so that the epitaxial wafer grown on the tray 5 can be heated evenly, and also ensure the stability of the flow field on the surface of the epitaxial wafer, thereby ensuring the growth quality of the epitaxial wafer.

[0026] The airway structure includes a plurality of longitudinal airways 30 located inside the large base 3 and transverse airways 31 connected to the longitudinal airways 30, wherein one longitudinal airway 30 corresponds to one transverse airway 31 as a separate airway structure. Taking the present embodiment as an example, three small bases 4 are arranged on the large base 3 in the present embodiment, so three separate airway structures are arranged inside the large base 3, wherein the transverse airway 31 is provided with a plurality of air outlets 32 connected to the upper surface of the large base 3. When epitaxial wafer production is carried out, the airflow flows into the transverse airway 31 through the longitudinal airway 30, then flows into the air outlet 32 ​​from the transverse airway 31, and finally is ejected from the upper surface of the large base 3, thereby driving the small base 4 to rotate. In order to ensure that the small base 4 can be driven by the ejected airflow, a plurality of airways are arranged at the bottom of the small base 4. shaped grooves 40, wherein the strip grooves 40 are in a polar array at the bottom of the small base 4, which is equivalent to the strip grooves 40 surrounding the array around the bottom of the small base 4. When the airflow is ejected from the bottom of the small base 4, the small base 4 will be subjected to an upward buoyancy due to the ejection of the airflow, and will float upward for a short distance, thereby reducing the friction between the small base 4 and the large base 3. The airflow is blocked by the strip grooves 40 at the bottom of the small base 4, and then the airflow overflows from the strip grooves 40 along the side of the small base 4, thereby generating a shear force on the side of the small base, and then the upward buoyancy of the airflow on the small base 4 and the shear force on the side of the small base 4 will generate a thrust on the small base 4, so it will push the small base 4 to realize self-rotation, thereby driving the epitaxial wafer grown on the tray 5 to rotate, so as to ensure the growth quality of the epitaxial wafer.

[0027] A plurality of annular grooves 20 are respectively provided on the lower heating ring 2, wherein the bottom of the large base 3 is respectively provided with a plurality of convex rings 34 corresponding to the annular grooves 20, and the rotation of the large base 3 on the lower heating ring 2 is realized by limiting the rotation between the convex rings 34 and the annular grooves 20, wherein the airway structure also includes a plurality of first annular airflow channels 33 provided at the bottom of the large base 3, wherein each longitudinal airway 30 is correspondingly connected to a first annular airflow channel 33, wherein the first annular airflow channel 33 is arranged between adjacent convex rings 34, and a plurality of second annular airflow channels 21 are also provided on the lower heating ring 2, and the second annular airflow channels 21 are located between two adjacent annular grooves 20, wherein each second annular airflow channel 21 is provided with a separate air inlet 22 connected thereto, wherein the air inlet 22 can be connected to an external air source through an air pipe for supplying air to the air inlet 22, and when the convex ring 34 is limitedly matched with the annular groove 20, it is equivalent to the large base. After being installed between 3 and the lower heating ring 2, an annular airflow chamber 23 is formed between the first annular airflow channel 33 and the second annular airflow channel 21, which is equivalent to the longitudinal airway 30 in the large base 3 being connected to the annular airflow chamber 23. When it is necessary to drive the small base 4 to rotate, the air is supplied to the air inlet 22 in the lower heating ring 2 through the air source from the outside using the air pipe. The gas enters the annular airflow chamber 23 through the air inlet 22, and then flows into the longitudinal airway 30, and finally enters the transverse airway 31 and is ejected from the air outlet 32 ​​in the transverse airway 31, and finally is ejected from the upper surface of the large base 3 to drive the small base 4 to rotate. Taking this embodiment as an example, this embodiment has three separate airway structures, so three separate air inlets 22 are provided in the lower heating ring 2, wherein each air inlet 22 is independently supplied with air to drive the separate small base 4 to rotate, thereby facilitating the control of the separate rotation of each small base 4, and further facilitating the separate growth of each epitaxial wafer.

[0028] A rotating shaft 35 connected to the large base 3 is also provided at the bottom thereof, wherein the rotating shaft 35 passes through the lower heating ring 2 and rotates with the lower heating ring 2. By passing the rotating shaft 35 through the lower heating ring 2 and connecting with the bottom of the large base 3, the large base 3 can be driven to rotate on the lower heating ring 2 through the rotating shaft 35.

[0029] A plurality of limit grooves 36 are provided on the surface of the large base 3, and a latch 37 is provided in the middle of the limit groove 36. The small base 4 is located in the limit groove 36 and is rotatably connected to the latch 37, so the small base 4 is rotatably connected to the latch 37 to realize a rotatable connection in the limit groove 36 in the large base 3, wherein the gas outlet end of each airway structure is located in a different limit groove 36, so that each airway structure can independently control the rotation of a small base 4, thereby facilitating the control of the rotation speed of each small base 4 by controlling the flow rate of the gas, thereby facilitating the independent control of the growth of each epitaxial wafer.

[0030] The lower heating ring 2 is also provided with an upstream protective plate 24, a downstream protective plate 25 and a transition piece 26 for the reaction gas to flow in. A gas passage cavity 28 is provided in the middle of the transition piece 26. A gas guide slope 27 is provided at one end of the upstream protective plate 24, wherein the lower side of the gas guide slope 27 corresponds to the gas passage cavity 28, and the downstream protective plate 25 is arranged on the side away from the transition piece 26. When epitaxial wafer growth is required, the reaction gas is blown in through the gas passage cavity 28 in the middle of the transition piece 26, and the gas guide slope 27 of the upstream protective plate 24 guides the reaction gas into the reaction chamber 10 located between the upper heating ring 1 and the lower heating ring 2 so as to be used for the growth of the epitaxial wafer. By providing the gas guide slope 27, it is easier to introduce the reaction gas into the reaction chamber 10.

[0031] A central protective plate 29 is also provided at the end of the lower heating ring 2 close to the downstream protective plate, and the large base 3 is located between the upstream protective plate 24, the downstream protective plate 25 and the central protective plate 29, wherein side baffles 6 are provided on both sides of the lower heating ring 2, and the upper ends of the side baffles 6 are connected to the upper heating ring 1. The upper heating ring 1 and the lower heating ring 2 are connected by the side baffles 6, so that the upper heating ring 1 and the lower heating ring 2 and the side baffles 6 enclose a reaction chamber 10.

[0032] A circumferential cover plate 7 and a central cover plate 8 are respectively provided on the upper surface of the large base 3, wherein the circumferential cover plate 7 is a number of separate small modules. After all the circumferential cover plates 7 are spliced ​​together and installed, corresponding through holes 9 will be provided in the middle corresponding to the limiting grooves 36, so as to facilitate placing the tray 5 on the small base 4, and a certain height gap is left between the circumferential cover plate 7 and the bottom of the limiting grooves 36, which can ensure that the small base 4 can be rotated by gas in the limiting grooves 36, and a circle of anti-slip rings 41 will be provided on the side of the small base 4. When the small base 4 is rotatably installed in the limiting grooves 36 by the latch 37, the diameter of the anti-slip ring 41 is larger than the diameter of the through hole 9, so as to prevent the small base 4 from detaching from the latch 37 and flying out due to excessive rotation speed when the gas pushes the small base 4 to rotate in the limiting grooves 36, resulting in production accidents.

[0033] The working principle of the present invention is as follows: a plurality of small bases 4 are provided on a large base 3 to rotate with the large base 3, and a tray 5 for placing substrate raw materials to grow epitaxial wafers is placed on each small base 4, and a plurality of airway structures are also provided in the large base 3, and each airway structure drives a corresponding small base 4 to rotate. In this way, when producing epitaxial wafers, since each airway structure can independently drive its corresponding small base 4 to rotate, when the substrate is placed on the tray 5 located above the small base 4 for epitaxial wafer growth, the synchronous production of multiple epitaxial wafers can be achieved at the same time, thereby improving production efficiency; and each small base 4 is driven to rotate by air supply from a separate airway structure, so that the temperature and flow field on the surface of each epitaxial wafer can be ensured to be uniformly distributed, thereby ensuring the growth uniformity of the epitaxial wafers, and further improving production quality.

[0034] Finally, it should be noted that the above description is only a preferred example of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A multi-wafer epitaxial furnace chamber structure, comprising an upper heating ring and a lower heating ring connected to the upper heating ring, characterized in that: The lower heating ring is provided with a large base for rotationally cooperating therewith, and the large base is provided with a plurality of small bases for rotationally cooperating therewith, and each of the small bases is provided with a tray for placing raw material growth epitaxial wafers, and the large base is provided with a plurality of airway structures, and each of the airway structures drives a corresponding small base to rotate.

2. The multi-wafer epitaxial furnace chamber structure according to claim 1, characterized in that: The airway structure includes a plurality of longitudinal airways located inside the large base and transverse airways connected to the longitudinal airways, wherein the transverse airways are provided with a plurality of air outlet holes connected to the upper surface of the large base, and the airway structure also includes a plurality of first annular airway channels provided at the bottom of the large base, and the longitudinal airways are connected to the first annular airway channels.

3. The multi-wafer epitaxial furnace chamber structure according to claim 1, characterized in that: A plurality of strip grooves are arranged at the bottom of the small base, and the strip grooves are arranged in a polar axis array at the bottom of the small base.

4. The multi-wafer epitaxial furnace chamber structure according to claim 2, characterized in that: The lower heating ring is respectively provided with a plurality of annular grooves, and the bottom of the large base is respectively provided with a plurality of convex rings corresponding to the annular grooves. The convex rings are rotationally matched with the annular grooves, and the first annular airflow channel is arranged between adjacent convex rings.

5. The multi-wafer epitaxial furnace chamber structure according to claim 4, characterized in that: The lower heating ring is provided with a plurality of second annular airflow channels, and the second annular airflow channels are located between two adjacent annular grooves. Each of the second annular airflow channels is provided with an air inlet channel communicating therewith, and the air inlet channel is connected to an external air source. After the convex ring and the annular groove are limitedly engaged, an annular airflow chamber is formed between the first annular airflow channel and the second annular airflow channel.

6. The multi-wafer epitaxial furnace chamber structure according to claim 1, characterized in that: The bottom of the large base is provided with a rotating shaft connected thereto, and the rotating shaft passes through the lower heating ring and is rotatably matched with the lower heating ring.

7. The multi-wafer epitaxial furnace chamber structure according to claim 1, characterized in that: The surface of the large base is provided with a plurality of limiting grooves, and a latch is provided in the middle of each limiting groove. The small base is located in the limiting groove and is rotatably connected to the latch. The air outlet end of each airway structure corresponds to a limiting groove.

8. The multi-wafer epitaxial furnace chamber structure according to claim 1, characterized in that: The lower heating ring is also provided with an upstream protective plate, a downstream protective plate and a transition piece for the reaction gas to flow in, one end of the upstream protective plate is provided with a gas guide slope, the transition piece is provided with a gas passage cavity, and the gas guide slope is arranged corresponding to the gas passage cavity.

9. The multi-wafer epitaxial furnace chamber structure according to claim 8, characterized in that: The lower heating ring is also provided with a central protective plate at the end close to the downstream protective plate, the large base is located between the upstream protective plate, the downstream protective plate and the central protective plate, and side baffles are provided on both sides of the lower heating ring, and the upper ends of the side baffles are connected to the upper heating ring.

10. The multi-wafer epitaxial furnace chamber structure according to claim 7, characterized in that: The upper surface of the large base is also provided with a circumferential cover plate and a central cover plate, respectively. A through hole is provided between the circumferential cover plate and the central cover plate corresponding to the limiting groove. The side of the small base is provided with an anti-slip ring, and the diameter of the anti-slip ring is larger than the diameter of the through hole.

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